649261908 has 18 divisors (see below), whose sum is σ = 1641189914. Its totient is φ = 216420624.

The previous prime is 649261867. The next prime is 649261913. The reversal of 649261908 is 809162946.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 484088004 + 165173904 = 22002^2 + 12852^2 .

It is a tau number, because it is divible by the number of its divisors (18).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 9017491 + ... + 9017562.

Almost surely, 2^649261908 is an apocalyptic number.

It is an amenable number.

649261908 is an abundant number, since it is smaller than the sum of its proper divisors (991928006).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

649261908 is a wasteful number, since it uses less digits than its factorization.

649261908 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18035063 (or 18035058 counting only the distinct ones).

The product of its (nonzero) digits is 186624, while the sum is 45.

The square root of 649261908 is about 25480.6182813526. The cubic root of 649261908 is about 865.9111021043.

The spelling of 649261908 in words is "six hundred forty-nine million, two hundred sixty-one thousand, nine hundred eight".